Tekno RC "M5" Hardened Steel 5mm Bore Mod 1 Pinion Gear. Tekno RC M5 Pinion Gears stand out from the rest. These are the ultimate pinions for 1/8th Electric and any other MOD1 pinion application. With sizes ranging from 11T all the way to 30T, you are sure to find the right gear ratio for racing or those insane speed runs. The M5 set screw ensures that your gear will stay put during operation and ensure you won't strip it...